AB1458 TREATMENT UTILIZATION, SYMPTOMS, AND COMORBIDITIES IN DERMATOMYOSITIS: AN ANALYSIS OF ELECTRONIC MEDICAL RECORDS IN THE UNITED STATES
Authors: A. Kielhorn, Z. Wang, K. Moy, L. Christopher Stine, I. E. Lundberg, H. Chinoy, K. Gunter, R. Aggarwal
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> Dermatomyositis (DM) is a rare, chronic inflammatory disease characterized by skin manifestations and/or progressive muscle weakness and other systemic manifestations. Prior analyses have reported higher morbidity, hospitalization rates, and mortality among patients with DM compared with matched controls<sup>[1-3]</sup>; however, more recent data on the disease burden and treatments for DM are warranted. <h3>Objectives</h3> We conducted this analysis to provide updated data on the treatment utilization, symptoms, and comorbidities recorded for patients with myopathic DM in the United States. <h3>Methods</h3> This was a descriptive, retrospective cohort analysis that used TriNetX US electronic medical records (EMR) of adults who had been diagnosed myopathic DM (ICD-9 codes: 710.3/ICD-10: M33.1x, M33.9x, M36.0) between 1 January 2007 and 1 September 2020. Key inclusion criteria were: age ≥18 years at index date (i.e., date of DM diagnosis), ≥6 months of baseline data before the index date, and ≥6 months of follow-up after the index date. Assessments included utilization rates for medications of interest prior to the index date, percentage of patients who received ≥2 consecutive unique non-steroidal immunosuppressive therapies within 12 months of the index date, classification and qualification of the most common post-index symptoms and comorbidities, along with their comparison to pre-index values. <h3>Results</h3> The TriNetX database contained 1097 patients with DM (mean age: 54.6 years; sex: 77% female). The mean observation period was 9.7 years (6.0 years pre-index; 3.7 years post-index). Prior to the DM index date, 60% of patients were prescribed steroids and 24% were prescribed ≥1 non-steroidal immunosuppressive therapy. Within 3, 6, and 12 months of index date, 8%, 14%, and 20% of patients, respectively, received ≥2 immunosuppressive therapies (ISTs). A 2–3-fold increase in percentage was seen post-index compared with pre-index for a wide range of symptoms and comorbidities, including gastroesophageal reflux disease (43% and 22%, respectively), anxiety (25% and 13%), interstitial lung disease (26% and 10%), and osteoporosis (21% and 6%). <h3>Conclusion</h3> In this analysis of TriNetX EMR data, the majority of patients who were diagnosed with myopathic DM had received immunosuppressive therapies for an extended time to treat their symptoms before they received a formal DM diagnosis, which may have contributed to the delay in DM diagnosis. One fifth of patients had received ≥2 ISTs within 12 months of DM diagnosis, suggesting that even after receiving standard of care treatments, many patients experience DM symptoms that are difficult to control and/or tolerate. A wide range of symptoms and comorbidities increased post-DM diagnosis. These results highlight the remaining unmet need for earlier diagnosis and therapies that better control symptoms for patients with myopathic DM. <h3>References</h3> [1]Bradford Rice et al. J Med Econ 2016;19(7):649-654. [2]Aggarwal et al. Healthcare Resource Utilization and Costs of Dermatomyositis and Polymyositis in the US: A Systematic Literature Review. Poster presented at 2021 ACR Convergence Virtual Meeting; Nov 5-9, 2021. [3]Kronzer et al. Arthritis Care Res (Hoboken). 2021; doi: 10.1002/acr.24786. Online ahead of print. <h3>Acknowledgements</h3> Editorial support was provided by Korie Handwerger of Alexion, AstraZeneca Rare Disease (Boston, MA). <h3>Disclosure of Interests</h3> Adrian Kielhorn Employee of: Alexion, AstraZeneca Rare Disease, Zheng Wang Employee of: Alexion, AstraZeneca Rare Disease, Kristin Moy Employee of: Alexion, AstraZeneca Rare Disease, Lisa Christopher Stine Consultant of: UCB; Janssen; Octapharma; Boehringer-Ingelheim; Mallinckrodt; EMD Serono; Roivant/Priovant; Pfizer; ArgenX; Alexion, AstraZeneca Rare Disease; Horizon Therapeutics; and Allogene, Grant/research support from: Pfizer, Corbus and Kezar, Ingrid E. Lundberg Shareholder of: Roche and Novartis, Hector Chinoy Speakers bureau: UCB and Biogen, Consultant of: Alexion, AstraZeneca Rare Disease; Novartis; Eli Lilly; Orphazyme; and AstraZeneca, Grant/research support from: Eli Lilly and UCB, Kaniah Gunter: None declared, Rohit Aggarwal Consultant of: Alexion, AstraZeneca Rare Disease; Pfizer; Octapharma; CSL Behring; BMS; Argenx; Corbus; EMD; Janssen; Kezar; Kyverna; Roivant; and Mallinckrodt, Grant/research support from: Pfizer, BMS, Q32, EMD Serono, and Mallinckrodt and has served as a global principal investigator or site investigator for clinical trials sponsored by Kezar, Octapharma, CSL Behring, BMS, Corbus, and Pfizer.